Board Thread:General Discussion/@comment-30659386-20161202151148/@comment-30458103-20161203201352

Well you can't get Eevee unless you pre-paid Pokémon Brick Bronze so Charmander is most likely more rare.

Yamask is most likely better.

And shiny pokémon don't make a difference in stats, they just have a different appearance and glitter whenever they enter combat.